Computer systems using graphical user interface (GUI) systems, such as Microsoft® Windows, are optimized for accepting user input from one or more discrete input devices such as a keyboard (for entering text), and a pointing device (such as a mouse) with one or more buttons for activating user selections. Stylus-based user interfaces are input devices that provide the user with printed paper-type functionality. One approach for the stylus-based user interface is to use resistive technology (common in today's PDAs). Another approach is to use active sensors in a laptop computer.
Conventional stylus-based input devices include battery-operated writing instruments that allow the user to digitally capture a handwritten note or drawing. Such a stylus-based input device typically attaches to a Universal Serial Bus cradle that permits the user to upload handwritten notes or drawings to a computer system. These devices include a capture system that cooperates with special digital paper or a sensor board to digitally capture what the user has written. The capture system is specifically designed to read patterns on the digital paper or sensor board in order to interpret writing and paper position.
Conventional stylus-based input devices are dedicated to sensing movement and physical contact with a surface. They provide a singular type of functionality limited to writing, tapping, or otherwise contacting a surface, such as a computer screen, paper or a sensor board.